Crater Name  Location  Latitude  Longitude  Diameter (km)  Age (Ma)  Exposed  Drilled  Target Rock**  Bolide Type***
 Douglas  United States  N 42° 40'  W 105° 28'  0.15  ~280  Y N S  -




Kastning, H. and Huntoon, P.W. (1996) Cluster of five small Pennsylvanian meteorite impact craters on Sheep Mountain near Douglas, Wyoming. In NASA’s Wyoming Space Grant Fellowship Program 1995-6 Space Science Research: Graduate and Undergraduate Fellowship reports, edited by T.M. Ciardi and P.E. Johnson, University of Wyoming, Laramie, WY, pp 57–64.
Kenkmann, T., Sundell, K.A., and Cook, D. (2018) Evidence for a large Paleozoic Impact Crater Strewn Field in the Rocky Mountains. Sci Rep 8:13246.
* pre-1977 K-Ar, Ar-Ar and Rb-Sr ages recalculated using the decay constants of Steiger and Jager (1977) Ages in millions of years (Ma) before present.

** Abbreviations: C - Crystalline Target; C-Ms - Metasedimentary Target; M - Mixed Target (i.e.sedimentary strata overlying crystalline basement); S - sedimentary target (i.e. no crystalline rocks affected by the impact event). From Osinski. G. R., Spray J. G., and Grieve R. A. F. 2007. Impact melting in sedimentary target rocks: A synthesis. In The Sedimentary Record of Meteorite Impacts, Geological Society of America Special Paper. Editors: Evans K. Horton W., King D., Morrow J., and Warme J. Geological Society of America: Boulder, in press.

***From Koeberl,C. Identification of meteoritic components in impactites. 1998, Koeberl, C. The Geochemistry and Cosmochemistry of Impacts. 2007 and PASSC Files. (IAB, IIIAB, IIIB, IIID - Iron Meteorite)